Yves Brun and colleagues from Indiana University discovered that the world's strongest glue is produced by the bacterium Caulobacter crescentus to stick to river rocks.

The adhesive can withstand an enormous amount of stress, equal to the force felt by a quarter with more than three cars piled on top of it. That’s two to three times more force than the best retail glues can handle.

"There are obvious applications since this adhesive works on wet surfaces," said study leader Yves Brun, an Indiana University bacteriologist. "One possibility would be as a biodegradable surgical adhesive."

But making it has proved challenging. Like a mess of chewing gum, the gunk globs to everything, including the tools used to create it.